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Quantum Calorimeters Group

Superconducting devices at very low temperatures can be used to measure very small amounts of energy. Using this effect, the Quantum Calorimeters Group is building single photon detectors for large regions of the electromagnetic spectrum.

The Quantum Calorimeter Group in the Quantum Sensors Division develops and applies sensors that detect the energy of single photons and particles. These devices are typically fabricated from superconducting materials and achieve unprecedented energy sensitivity by leveraging certain unique properties of quantum mechanics and superconductivity. For example, Transition-Edge Sensors (TESs) are able to measure the energy of single x-ray and gamma-ray photons with a precision better than one part per thousand and Thermal Kinetic Inductance Detectors (TKIDs) are able to measure the energy of charged particles over several orders of magnitude with similar precision.

The group also develops complete spectroscopic measurement systems based on arrays of these superconducting microcalorimeter sensors. Working closely with the Quantum Electronics and Device Fabrication groups, the team develops custom multiplexed readout, cryogenics, x-ray windowing, acquisition and analysis software to enable arrays of hundreds to thousands of microcalorimeter pixels in a deployable instrument. These x-ray and gamma-ray spectrometers combine good spectral resolving power and good collecting efficiency in a way that is not possible with other detector technologies, enabling new measurement modalities. Our microcalorimeter spectrometers are being implemented in experiments at synchrotron beamlines, particle accelerators, nuclear analysis labs, table-top x-ray systems, and suborbital balloons. These detectors are providing new measurement capability for a wide range of applications including materials analysis, quantum information, astrophysics, microelectronics defect analysis and supply chain verification, and the accumulation of atomic and nuclear reference data for industry and nuclear security.

News and Updates

Just for KICS!

Sensors capable of detecting individual photons of visible light have become essential for applications ranging from imaging faint galaxies to quantum computing

Projects and Programs

Kinetic Inductance Spectrophotometry

Ongoing
Within this application space, the transition-edge sensor (TES) microcalorimeter is the most mature technology, with demonstrated x-ray energy resolving capabilities of better than a part per thousand. Current TES readout techniques require the use of superconducting quantum interference device

Microcalorimeter Spectrometers for X-ray and Gamma-ray Spectroscopy

Ongoing
The Quantum Calorimeters Project in the Quantum Sensors Group develops and applies sensors that detect the energy of single photons or particles. For example, Transition-Edge Sensors (TESs) are able to measure the energy of single x-ray and gamma-ray photons with a precision better than one part per

Nanoscale, Element-Specific X-ray Imaging for Integrated Circuit Metrology

Ongoing
Industry roadmaps identify the characterization of nanoscale subsurface feature shape and composition as a measurement need for the semiconductor industry. However, IC interiors are difficult to probe post-manufacturing due to the presence of many close-packed and nanoscale subsurface features, of

Publications

Spectroscopic Measurements and Models of Energy Deposition in the Substrate of Quantum Circuits by Natural Ionizing Radiation

Author(s)
Joseph Fowler, Paul Szypryt, Raymond Bunker, Ellen Edwards, Ian Fogarty Florang, JIANSONG GAO, Shannon Hoogerheide, Ben Loer, Hans Mumm, Nathan Nakamura, John Orrell, Elizabeth M. Scott, Jason Stevens, Daniel Swetz, Brent VanDevender, Michael Vissers, Joel Ullom
Naturally occurring background radiation is a potential source of correlated decoherence events in superconducting qubits that will challenge error-correction

Kinetic inductance current sensor for visible to near-infrared wavelength transition-edge sensor readout

Author(s)
Paul Szypryt, Douglas Bennett, Ian Fogarty Florang, Joseph Fowler, Jiansong Gao, Andrea Giachero, Ruslan Hummatov, Adriana Lita, John Mates, Sae Woo Nam, Daniel Swetz, Joel Ullom, Michael Vissers, Jordan Wheeler
Single-photon detectors based on the superconducting transition-edge sensor are used in a number of visible to near-infrared applications, particularly for

Few-electron highly charged muonic Ar atoms verified by electronic K xrays

Author(s)
Takuma Okumura, Toshiyuki Azuma, Douglas Bennett, W. Bertrand (Randy) Doriese, Malcolm Durkin, Joseph Fowler, Johnathon Gard, Tadashi Hashimoto, Ryota Hayakawa, Yuto Ichinohe, Paul Indelicato, Tadaaki Isobe, Sohtaro Kanda, Daiji Kato, Miho Katsuragawa, Naritoshi Kawamura, Yasushi Kino, Nao Kominato, Yasuhiro Miyake, Kelsey Morgan, Hirofumi Noda, Galen O'Neil, Shinji Okada, Kenichi Okutsu, Nancy Paul, Carl D. Reintsema, Toshiki Sato, Dan Schmidt, Kouichiro Shimomura, Patrick Strasser, Daniel Swetz, Tadayuki Takahashi, Shinichiro Takeda, Soshi Takeshita, Motonobu Tampo, Hideyuki Tatsuno, Tong Xiao-Min, Joel Ullom, Shin Watanabe, Shinya Yamada, Takuma Yamashita
Electronic K x rays emitted by muonic Ar atoms in the gas phase were observed using a superconducting transition-edge-sensor microcalorimeter. The high

Awards

Patents

X-Ray Spectrometer

X-Ray Spectrometer

NIST Inventors
Kevin L. Silverman , Carl D. Reintsema , Galen O'Neil , Luis Miaja Avila , Daniel Swetz , W.Bertrand (Randy) Doriese , Dan Schmidt , Bradley Alpert , Joseph Fowler , Joel Ullom and Ralph Jimenez
This invention includes: an x-ray plasma source that produces primary x-rays; an x-ray optic that transmits and focuses the primary x-ray onto a sample jet from which fluorescence x-ray are emitted; and a microcalorimeter array detector that measures the energy of the incoming fluorescence x-rays

Contacts

Group Leader